Studies of medical technology are usually performed in academic institutions or major medical centers. In some instances the results from these studies may not apply to community hospitals. An alternative are studies based on data from community hospitals. One source of such data that is becoming increasingly available is the detailed clinical information that is routinely collected and electronically stored for monitoring the quality of medical care. This source not only makes it possible to evaluate technology in community hospitals as well as in teaching hospitals but also may reduce the cost of technology assessment. The primary goal of the proposed research is to determine whether data used for monitoring the quality of medical care, Medisgroups, is valuable for assessing coronary artery revascularization procedures (angioplasty and bypass surgery). A secondary goal is to identify the types of hospitals that best perform the revascularization procedures. Two data sets that are currently resident on the applicant's computer will be used for the analyses: 1) The first was collected by the Health Care Financing Administration, HCFA, using the Medisgroups method on a random sample of 3003 patients from 211 hospitals in seven states that had a coronary artery revascularization procedure in 1985. These data were merged with other HCFA data sets that had information on patient survival and subsequent hospitalizations. 2) The second data set is from the American Hospital Association. It contains more than 900 items of information on each U.S. hospital. Analyses will be performed for each revascularization procedure to identify risk factors for each of several adverse outcomes including short and long term mortality, long hospital stay, renal failure, and perioperative myocardial infarction. The revascularization procedures will be compared on the basis of charges and the rate of an adverse outcome for the types of patients treated. Other analyses will test whether the charges and rates of adverse outcomes adjusted for the types of patients treated vary according to hospital characteristics. The study should help clarify some of the advantages and disadvantages of technology assessment using data collected for the purpose of monitoring quality of care.